1. Technical Field of the Invention
The present invention relates to drain valves. More particularly, the present invention relates to a drain valve for use on a pressure trap outlet port of an air conditioner unit, wherein condensation is prevented from freezing therein.
2. Description of the Related Art
One function performed by air conditioning units used in many homes and businesses is to reduce the specific humidity of air located within the home or business. This process is typically accomplished by drawing the humid air into the air conditioning unit, removing moisture therefrom and blowing the less-humid air back into the home or business. The extracted moisture typically condenses within portions of the air conditioning unit, such as, for example, the pressure-trap outlet port, where it may freeze if subjected to a below-freezing surrounding temperature.
In the case of an air conditioner pressure-trap, the outlet port must be sealed during operation of the air conditioning unit to provide sufficient internal pressure drop to pump the air through the air conditioning unit. Whatever condensation which accumulates within the pressure-trap is not permitted to automatically drain therefrom. In the event the temperature of the air surrounding the pressure-trap drops below freezing, the condensation accumulated therein may freeze, thereby causing rupture or other damage thereto. Thus, it is desirable to provide a drain valve for use on an outlet end of an air conditioner pressure-trap, wherein the drain valve permits condensation to drain therefrom when the surrounding air temperature reaches a predetermined threshold value.
For example, U.S. Pat. No. 4,809,727 to Chamberlin teaches a thermally-activated drip valve for use on a standard outdoor faucet to prevent freezing of water therein, wherein a flow of water draining therethrough regulates opening and closing of the drip valve. However, it is further desirable to provide a drain valve wherein opening and closing thereof is activated in response to the temperature of the surrounding air and independently from the rate of flow of water or condensation therethrough.